Cognitive predictors of everyday functioning in older adults: results from the ACTIVE Cognitive Intervention Trial

Abstract

Objective: The present study sought to predict changes in everyday functioning using cognitive tests.

Methods: Data from the Advanced Cognitive Training for Independent and Vital Elderly trial were used to examine the extent to which competence in different cognitive domains--memory, inductive reasoning, processing speed, and global mental status--predicts prospectively measured everyday functioning among older adults. Coefficients of determination for baseline levels and trajectories of everyday functioning were estimated using parallel process latent growth models.

Results: Each cognitive domain independently predicts a significant proportion of the variance in baseline and trajectory change of everyday functioning, with inductive reasoning explaining the most variance (R2 = .175) in baseline functioning and memory explaining the most variance (R2 = .057) in changes in everyday functioning.

Discussion: Inductive reasoning is an important determinant of current everyday functioning in community-dwelling older adults, suggesting that successful performance in daily tasks is critically dependent on executive cognitive function. On the other hand, baseline memory function is more important in determining change over time in everyday functioning, suggesting that some participants with low baseline memory function may reflect a subgroup with incipient progressive neurologic disease.

Figures

Figure 1.

Parallel process latent growth model of cognition and functional ability. Parallel process latent growth model of everyday functioning and cognitive domains (memory, reasoning, processing speed, and global cognition) across six measurement occasions in the Advanced Cognitive Training for Independent and Vital Elderly study. The model is described notationally in the text. Latent variable intercepts and slopes for everyday functioning are regressed on covariates. Residual variances for the everyday functioning latent variables are shown by smaller arrows going toward the latent (circled) variables. Numbers on arrows going from latent growth parameters to observed time points indicate factor loadings. C = observed composite cognitive score at a measurement occasion. F = observed composite everyday functioning score at a measurement occasion.